This proposal defines the need for the development of a device involving safe, rapid and uniform heating to thaw frozen blood and blood components. This device would result in a therapeutically effective product that would reduce the risk of contamination and damage, and significantly increase allowable storage time. Rapid thawing (i.e., less than 5 minutes) is essential. The proposed rapid thawing technique employs an active microwave array in conjunction with radiometric sensing. Each element of the array is, basically, a dual-mode transducer allowing simultaneous microwave heating and radiometric temperature sensing, and further allowing independent control of power at each element. The development and integration of the multi-element array will include the capability to monitor and control the temperature of the entire blood unit. This device for the rapid thawing of frozen blood and blood components may be integrated into a total closed-cell preparation system which includes other functions, such as sterile docking, cell washing and in-line warming. The device is consistent with the NIH objective of developing "equipment and procedures for the collection, separation, processing, preservation, storage and distribution of blood and blood components." PROPOSED COMMERCIAL APPLICATIONS: This device would result in improved health care at significant cost savings since blood components would no longer be thawed well in advance of the need.